Twister cap



May 3, 1938. l w. B. AcvzooFER l 2,116,342

TWISTER `CAP Filed Oct. 20, 1957 Patented May 3, 1938 Wilfrid B. Cooper, Rome, Ga.,

Chatillon v Corporation,

poration of Delaware assignor to Tubize New York, N. Y., a cor- Appucation october 2o, 1937, serial' No. 169,957

3 Claims.

This invention relates to atwister cap fo' o twisting bobbins of the type which gripplngly `engages the bobbin under the action of centrifugal force.L 'The invention aims to provide an im- 5 proved twister cap of this character having a rigid body-member of hard or resilient material adapted to engage a bobbin spindle and a yieldable contact or gripping member iixed to the rigid body-member which is adapted to expand when the cap is rotated and engage the bobbin circumferentially. i

The twister cap of the invention is especially adapted for "upstroke twisting apparatus and comprises a rigid body-member formed of any suitable hard material, such as metal, or molded thermoplastic material; for example vulcanized rubber or the like, having a central bearing surface for engaging a spindle blade, and an annular j portion having a substantially iiat surface for '20 engaging the yieldable member. In its more complete form, the rigid member has a bored sleeve for engaging the spindle blade, a disclike portion attached to the sleeve and an annular overhanging lip depending from the disclike portion which is adapted to surround the upper outer edge oi the bobbin. .The yieldablev member is preferably formed of soft or highly elastic rubber and is preferably xedly attached to the rigid member. as by bonding, certenting, 3c vulcanizing, or the like. The yieldable member is adapted to fit inside of the bobbin when the cap is in engagement with the spindle. In a particularly eillcacious construction in accordance with the invention, the rigid body-member is formed of hard rubber and the yieldable member is a piece of relatively thick, hat, soft rubber, bonded on one side to the at surface of the rigid member. The yieldable rubber-member is preferably circular in section and of sufiiclent thickness that the free or unattached portion thereof may be expanded or thrown outwardly under the 2 action of centrifugal' force and brought into cir cumferential engagement with the inner surface of the bobbin. The yieldable rubber-member is preferably-split or otherwise separated for a short distance inwardly from the outer peripheral or bobbin engaging surface, thereby leaving a suitable portion of the free or unattached part of the rubberto engage the bobbin more or less inde- 5o pendently of the remaining portion.

In the accompanying drawing, Fig- 1 S110' a sectional view of a twister cap in accordance with the invention; and

Fig. 2 shows a twister cap similar t0 that-illustrated in Fig. l in engagement with a `bobbin.

In the drawing, the twister cap l comprises an annular rigid body-member 2 formed of any suitable hard material, preferably molded plastic A material or vulcanized rubber, having a disc-like portion 3 with substantially at upper and under 5 surfaces and an overhanging or depending lip 4 having a curved outer surface which preferably joins the at top tangentially. The top and curved surfaces of the lip-are highly polished to prevent any entangling of the thread during 10 twisting. The rigid -member 42 has a depending sleeve 5 which is bored out at the center to provide a suitable spindle mounting, for example, on the blade of the spindle. When the rigid member is formed of rubber or the like, the bore 15 is preferably provided with a metal liner 6 for engaging the end of the spindle blade 1. 'I'he liner makes a close lit with the spindle blade but is free to turn or be vertically adjusted thereon.

'I'he yieldable member 8 is formed of a rela-V tively thick and preferably iiat piece of elastic rubber and is suitably fixed to the rigid member as by bonding during vulcanization, preferably over the entire annular area of contact. The piece of yieldable rubber is preferably ringlike, 26 being open at the center, and having an outer diameter `slightly less than the inner diameter of -the bobbin il. The outer periphery i0 of the exible member isl preferably in the form of the frustum of a cone and tapers inwardly in the w direction of its free or unattached outer surface il. In a preferred construction, the' yieldable rubber member is slit or otherwise divided into two portions from the peripheral surfacelll inwardly a suitable distance as shown by the line i5, thereby leaving the upper or bonded part it in rm engagement with the disc-like portion 3 and the lower part il highly yieldable under the action of centrifugal force when the twister cap isrotated. y

The spindle blade 'i is of the conventional construction in use on "upstroke twisting machines and is rotated at a high speed by the usual means. The lower portion of the spindle blade is provided with any suitable spindle-driving device I8 and a e l@ for driving the bobbiri 9.

The twister cap of the invention may be formed in a single vulcanizing operation in which the rigid member is formed oi' one kind ofV rubber and the yieldable member of a different kind of rubg@ ber.

In using the twister cap of the invention, the bobbin` 9. carrying a cake of substantially dry, untwisted rayon thread, is mounted on the base i9. This member is in rotatable engagement with the spindle and in frictional gripping engagement with the bobbin. The twister cap is then placed over the upper end of the spindle 1 and when the proper vertical position is reached, the yieldable member fits inside the bobbin and the disc-like portion rests upon the bobbin top. The spindle and, of course, the spindle blade are then rotated at a high rate of speed, for example, at from 5000 to 6000 R. P. M. per minute and the twister cap is rotated therewith. Under the action of the centrifugal force imposed upon the system, the yieldable member 8 and particularly the lower or free end part I1, is displaced outwardly, as shown in Fig. 2, thereby bringing the peripheral portion Ill into gripping engagement with the inner cylindrical surface of the spinning bobbin 9. As a consequence of this action, the yieldable member. serves asv an automatic clutch, locking the bobbin to the twister cap.

'Ihe twister cap of the invention, especially in the form illustrated in the drawing,may be regarded as a unitary or one-piece structure or device. By reason of the intimate contact of the yieldable member with the rigid member of the cap there is no dislocation of the parts and resulting unbalancing during rotation. Loose or free moving parts in twister caps as heretofore constructed cause unbalancing and objectionable vibrations which injure the twisting apparatus and frequently cause the cap or parts thereof to be hurled into the twisting room.v The yieldable member bears a fixed relation to the remainder of thercap and when the cap is centered on the spindle blade, the yieldable member is likewise similarly centered.

The yieldable member contacts the bobbin in such manner that there is no opportunity for the hard or rigid part to engage the bobbin and be ground into a ne powder. When hard substances contact the bobbin, which is generally made of aluminum, black powder is formed which deposits on the yarn cake with resulting damage. Heretofore, the yarn has been damaged by the dark dust worn off the bobbin or cap and the present invention eliminates this objectionable condition` The twister cap of the invention is not only dynamidallystable but provides a uniform grip' between the flexible member and the bobbin. The exible member is free to expand and contract uniformly without restraint or friction and the peripheral edge is therefore always in the proper relation to the other portions of the cap. There are no contacting or supporting elements preventing free action of the yieldable member.

I claim:

1. A twister cap for bobbin twisting machines which comprises a rigid member adapted to be rotatably mounted upon a bobbin spindle, and a relatively thick piece of yieldable rubber bonded on one of its sides to the rigid member which has a peripheral bobbin-contacting surface and is adapted to fit inside the bobbin when the cap opening, and an annular relatively thick yieldable rubber member bonded on one of its sides to the annular surface of the rigid member, said rubber member being annularly slit and having a bobbin-contacting surface adapted to t inside the bobbin and to be thrown outwardly during rotation into pressed peripheral engagement with the bobbin.

3. A cap adapted toengage the upper endportion of a cylindrical bobbin which is mounted upon thespindle base of a conventional upstroke twisting machine, comprising a rigid member having a lip adapted to overhang the bobbin, a central opening for engaging a spindle blade and an annular portion between the lip and the opening having an under surface and a smooth upper surface which extends to and joins the surface of the lip, and an annular relatively thick piece of rubber bonded on one of its sides to the under surface of the rigid member which is adapted to fit inside the bobbin when the cap is mounted in operative position over the spindle blade, said piece of rubber being elastic and having a depending lower portion which is highly yieldable under the action of centrifugal force and adapted 'to be thrown into pressed engagement with t e inner circumferential'surface of the bobbin.

WILFRDD B. COOPER. 

